1. Field of the Invention
The present invention relates to a catheter which has two balloons, one of which carries a stent, and which is introduced into a patient for stent implantation.
Each of the two balloons can be expanded separately by supplying a fluid medium under pressure via an appropriate lumen in a tube-like basic body of the catheter to the balloon in question.
The catheter is used for the implantation of a stent in a patient. A stent is a tubular element, usually made of wire mesh, which can be expanded in cross-section direction. Such an element is for instance introduced into a blood vessel of a patient, of which the wall has been impaired to such a degree, that there is a risk of collapse of the blood vessel concerned. The stent is introduced in a compressed state and expanded when situated in the required position, thus supporting the wall of the blood vessel. Expansion is usually achieved by means of a balloon of a balloon catheter.
2. Description of the Related Art Including Information Disclosed under 37 CFR .sctn..sctn.1.97-1.99
A catheter of the type described above is known from European Published Patent Specification No. 0 260 107. The catheter described in this published patent specification comprises several dilatation balloons of increasing diameter.
Another catheter of this type with two balloons is known from U.S. Pat. No. 5,226,889. The relatively distal balloon is in this case a dilatation balloon, whereas the relatively proximal balloon is used for expanding a stent. This stent is arranged in a compressed state around the relatively proximal balloon and thus introduced into the body of the patient. By expanding the balloon, the stent, which will subsequently remain behind in the body of the patient, will also expand.
Other types of catheters with several balloons comprise, for instance, an occlusion balloon as a relatively distal balloon and a dilatation balloon as a relatively proximal balloon.
Various catheters that mount at least two balloons, that are used in the implantation of a stent or that are introduced into a blood vessel with the assistance of a guidewire are disclosed in the following listed, analogous and non-analogous, U.S. Patents and foreign and PCT patent publications:
______________________________________ Patentee ______________________________________ U.S. Pat. No. 4,148,307 Utsugi 4,762,129 Bonzel B1 4,762,129 4,990,139 Jang 5,002,532 Gaiser et al. 5,040,548 Yock 5,061,273 Yock 5,226,889 Sheiban 5,232,445 Bonzel 5,358,387 Miller 5,336,184 Teirstein German Patent Publications: DE 26 59 238 Utsugi DE 38 33 359 Bockenheimer, et al. European Patent Publications: EP 0 260 107 Jang EP 0 274 846 Rosenbluth EP 0 277 270 Gaiser et al. EP 0 245 051 Rosenbluth, et al. EP 0 442 657 Ryan et al. EP 0 528 039 Igaki et al. EP 0 595 308 Solar et al. PCT Publications: W0 93/20882 Motasim Sirhan et al. W0 93/21835 Nita et al. WO 94/02196 Lee ______________________________________